122
32059L–AVR32–01/2012
AT32UC3B
The flash controller supports flash blocks with up to 2^21 word addresses, as displayed in
Figure14-1. Reading the memory space between address pw and 2^21-1 returns an undefined result.
The User page is permanently mapped to word address 2^21.
Figure 14-1. Memory map for the Flash memories
14.4.5
Quick Page Read
A dedicated command, Quick Page Read (QPR), is provided to read all words in an addressed
page. All bits in all words in this page are AND’ed together, returning a 1-bit result. This result is
placed in the Quick Page Read Result (QPRR) bit in Flash Status Register (FSR). The QPR
command is useful to check that a page is in an erased state. The QPR instruction is much
faster than performing the erased-page check using a regular software subroutine.
14.4.6
Write page buffer operations
The internal memory area reserved for the embedded flash can also be written through a write-
only page buffer. The page buffer is addressed only by the address bits required to address w
words (since the page buffer is word addressable) and thus wrap around within the internal
memory area address space and appear to be repeated within it.
When writing to the page buffer, the PAGEN field in the Flash Command register (FCMD) is
updated with the page number corresponding to page address of the latest word written into the
page buffer.
Table 14-1.
User page addresses
Memory type
Start address, byte sized
Size
Main array
0
pw
words = 4pw bytes
User
2^23 = 8388608
w words = 4w bytes
0
pw - 1
pw
2^ 21+ 12 8
Unused
F
la
sh
dat
aarra
y
U n us ed
U s e r page
F las h w it h
e x t r a pa ge
2^ 21
A ll addr e s s e s ar e w o r d addr es s e s